A population of birds walks along the shores of a swampy area eating small crabs. Climatic changes cause the water level in the area to increase. Which genetic variation in the bird population will be at an advantance leading to greater survival in the area?

there is no correct list among the choices you've provided.

the list might look something like this:

-- baby human

-- piccolo

-- flute

-- soprano singer

-- trumpet

-- tenor singer

-- trombone

-- baritone singer

-- baritone horn

-- bass singer

-- tuba

since i had to make up the list myself, i made it easy on myself, and i didn't try to shuffle the string instruments and woodwinds into it too.